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Grant wrote: |
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>>>>> I recently disabled swap and mounted /tmp on tmpfs for a netbook since |
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>>>>> the SSD is so slow, and now I'm wondering if that would be a wise move |
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>>>>> for all of my Gentoo systems. In what type of situation would it be a |
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>>>>> bad idea? |
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>>>>> |
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>>>>> |
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>>>> Instead of disabling swap, just make it small (like 32MB or something; |
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>>>> whatever the smallest allowable partition size is). The kernel needs |
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>>>> swap to operate optimally, even if it's extremely small. Just make sure |
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>>>> it's there. |
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>>>> |
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>>>> |
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>>> Hmm, on this old box I noticed swap was using more than 135,000K earlier today |
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>>> as I was emerging xulrunner and ImageMagick. I think that the size of swap |
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>>> is relevant to the memory size that the box in question has. Not all |
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>>> machines have found their way to 2G RAM yet ... ;) |
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>>> |
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>>> |
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>>> |
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>> Don't forget that you can set swapiness too. This is set in |
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>> /etc/sysctl.conf and for mine I have this: |
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>> |
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>> vm.swappiness = 30 |
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>> |
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>> The lower the number, the less chance of it using swap. If it is set to |
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>> 90, it will use a lot of swap which is fine if you have little ram or a |
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>> really fast drive. If it is set to 30, then it will not use swap unless |
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>> it is basically out of ram. |
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>> |
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>> With the setting of 30, mine uses swap when compiling OOo or some other |
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>> large package or if I am opening a TON of pics. Otherwise, swap is at 0 |
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>> or close to it even after being up a long time. I have 2Gbs here tho. |
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>> Your mileage may vary. |
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>> |
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>> Dale |
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>> |
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> |
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> Thanks Dale. Should "vm.swappiness = 30" work well on all systems? |
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> My Gentoo systems have vastly different specs and duties so I love |
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> tweaks that always improve things. It sounds like /tmp on tmpfs is |
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> one of those. |
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> |
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> - Grant |
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> |
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> |
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> |
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|
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I'm on x86 and I really don't know where the vm part came from. It |
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could have been me that put it there but I think it may have gotten |
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updated somewhere along the way. I'm not sure what would update that |
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tho. May be worth a google for your arch and just swappiness and see |
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what else can be in front of it. |
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|
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I used to have it set to 70 when I only had 512MBs of ram. It would use |
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swap pretty regular, even just for caching stuff. So, the setting does |
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work for sure. If you wanted it to use swap only to prevent the system |
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from crashing, I would assume you could set it to 10 or something like |
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that. If you have a really fast drive, SATA or something, then you |
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could set it to 90 and let it use swap all it wants. |
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|
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Dale |
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|
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:-) :-) |
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